Effects of treatment application rates (fym and gypsum) on selected chemical properties of saline sodic soils under water limited condition in eastern lowlands Ethiopia

Abstract

A laboratory incubation experiment was carried out on saline sodic soils collected from Babile, Eastern Ethiopia to evaluate and compare the potentials of gypsum and farm yard manure (FYM) treatments for the reclamation of saline sodic soils. The treatment tested consisted of combination of six rates of gypsum (0, 25, 50, 75, 100 and 125% gypsum requirement) and four rates of farmyard manure (0, 10, 20 and 30 tons FYM ha-1) in a completely randomized design (CRD) replicated three times. Results revealed that sole and combined application of treatments significantly (P<0.001) improved soil pH, electrical conductivity saturated paste (ECe) and ESP over the control. Maximum reduction in soil pH (14.14%), ECe (48.99%) and ESP (16.20) recorded in soils treated with combined 30 tons FYM ha-1 and gypsum (125% GR) treatments. Furthermore, soils treated with sole application of gypsum at higher rates (50, 75,100 and 125% GR) achieved significantly higher reduction in soil pH, ECe and ESP than sole application of FYM. However, combined applications of FYM and gypsum were relatively more efficient than either one alone in removing exchangeable Na under condition of water limitation for dissolution. Hence, it may be concluded that all combinations of 20 and 30 tons FYM ha-1 with gypsum (50, 75,100 and 125% GR) rates reduced the soil pH, EC and ESP to agricultural permissible level.